Think of Drew Barrymore and you probably picture that radiant, rom-com-sweetheart's grin she has displayed for more than two decades. After watching her turn the world on with that smile, you understandably expect high-wattage Barrymore beaming when the star shows up in a Toronto hotel suite for an interview.

But on this particular day, Barrymore isn't smiling. At least not often. Sure, she is polite, feisty and, with the tips of her blond tresses newly dyed black, looking more than a little rock-and-roll. But above all else, the 34-year-old actress, producer and former child star turned Hollywood power player comes across as intense, all business even while wearing a playful pair of crimson platform pumps.

That's because the roller derby dramedy "Whip It," a movie she unveiled last month during the Toronto International Film Festival, marks the addition of yet another title on her lengthy résumé: director. And it's obvious she takes that job very seriously, even when answering the first (seemingly) innocuous question a reporter poses: How easy was it to slip into this new role behind the camera?

"I find that question refreshing because I'm always curious about the people who say, 'Why did you want to direct?,' " Barrymore says, her voice husky after several days of talking up "Whip It" nonstop. "And, 'Would you direct again?' I literally have this sort of anger when they ask me. Like, have you not read my bio? I started a [production] company 15 years ago. This is our 10th movie we've produced. Do you think it's a whim and an accident? I have been training for this for 10 to 15 years."

Clearly Barrymore feels invested in her work on "Whip It," a coming-of-age tale about a high-schooler (Ellen Page) who ditches the teen beauty pageant scene so she can speed and slam her way to victory in an Austin roller derby league. Barrymore, co-founder of that previously mentioned production company, Flower Films, says she immersed herself in every aspect of the filmmaking process, sleeping two or three hours per night during the shoot so she could weigh in on even minor creative decisions.

"Oh, I thought the first week I was going to die," she admits. "I was like, there is no question I am going to induce a heart attack on myself because I care so much."

While she obsessed over what was happening behind the scenes, Barrymore also had another part to play in front of the camera: that of fiery derby competitor Smashley Simpson, a gig that meant, like all of her skating co-stars, she had to endure intense training to learn how to compete like a legit roller girl.

"I had some bad bruises and bang-ups," she says, "but the hardest part for me was having to train and then go back into a production design meeting or a line producing meeting and cut budget and storyboard and shot-list."

Barrymore frequently sprinkles this sort of inside-moviemaking jargon into her comments. Another type of language that frequently tumbles out as she speaks? Profanities. Indeed, the little girl who insisted that E.T. be good and, later, battled and overcame drug and alcohol addiction has grown into a woman who doesn't mince (or censor) her opinions.

For example, she gets fired up when she talks about directors who park themselves by their video monitors instead of being close to their actors: "I don't respond to those people who are sitting by a monitor in their director's chair watching. I'm like, [expletive] you. I want it to be a passionate process."

And when asked if the current prevalence of buzzed-about films by female directors -- from Jane Campion's "Bright Star" to Lone Scherfig's "An Education" -- is evidence that more women can successfully break through in Hollywood, she insists that gender is no longer a barrier to cinematic success.

"I just call bull[expletive] on the whole female chip on the shoulder: 'We're repressed and men have all the power,' " she says. "Like, get over it. Make it happen for yourself, stop complaining, and P.S.? That chip on your shoulder is super unsexy. Like, you want something? Make it happen. Work hard."

Barrymore continues at great length about how women should feel empowered to do anything with their careers, a message she's savvy enough to note is also conveyed in "Whip It." She is at turns candid ("I never felt like, oh, I'm the young girl that's not going to get taken seriously. I was just astonished and grateful when I was.") and, always, intense.

But for a brief moment, she does drop the ultra-serious game face. When a reporter mentions that Barrymore and "Whip It," her labor of girl power love, were mentioned in a recent New York Times article about female filmmakers "taking charge" at the Toronto festival, her face instantly brightens.